The field of the present invention relates to surgical instruments. In particular, apparatus and methods are described herein for providing cooling of an energized surgical instrument.
A wide variety of energized surgical instruments (i.e., apparatus) are available. Some of these are described in:                U.S. Pat. No. 7,717,915 entitled “Ultrasonic coagulation and cutting apparatus” issued May 18, 2010 to Miyazawa and assigned to Olympus Medical Systems;        U.S. Pat. No. 7,909,824 entitled “Energy accessory” issued Mar. 22, 2011 to Masuda et al and assigned to Olympus Medical Systems; and        U.S. Pat. No. 8,147,488 entitled “Surgical operating apparatus” issued Apr. 3, 2012 to Masuda and assigned to Olympus Medical Systems.        
Generally, such an energized surgical instrument is held and actuated by a surgeon using a proximal handle portion; the surgical instrument engages tissue of the surgical patient at a distal portion that can include a probe, jaws, or other structural or functional members. One or more such members can be connected to a source of energy, e.g., ultrasonic, electrical, or other. The energy is transmitted distally along an energy conductor of the instrument to the distal portion to cut, seal, or coagulate selected tissues in the patient's body, typically by heating the tissue. The heat can be conducted from the distal portion of the surgical instrument into the tissue or, more typically, can be generated in the tissue by electrical or ultrasonic energy directed into the tissue by the distal portion of the surgical instrument. An elongated tube or sheath connects the proximal handle and the distal portion and can contain the energy conductor and optionally other members or components, e.g., for mechanically actuating the distal portion.